work sheet:

Task: assemble GI and PVC pipe work using screwed fittings.

Tools required

1. hack saw

2. tape measure

3. hand stock die

4. file

5. pipe cutter

6. pipe wrenches

7. Wire brush.

8. reamer

(a)   cut the pipe,

(b)  Thread

(c) wrap the threads with PTFE thread tape, onto the threads

(d)  Fix the fitting.

(e)  To fix the next fitting take the calculation

Length of pipe to be cut =L-2 (B-A) where L is the whole length given. B is the length from center of the fitting to the end of it and A is the length of the threads.

Revise the working drawing so as to come with the right work model.

The pipe work should be clean and the tee in the middle should face up and elbows in the right direction.

(f) To measure the pipe remaining, first insert the nipple and union.

(g)  measure the balance length to the tee.

(h) To tighten the union, pull up one side of pipe work to enable you tighten the piece .

(i)  Close the union lastly and make sure that the GI tees are at right angles.

(j) Confirm the entire dimensions of the base as you prepare to begin the PVC pipes.

(k) Thread cut the PVC pipes to size

(l) Fix them as shown one can first fix the elbows onto the pipes before fixing them onto the base.

(m) The final product!!!!!!!

(n) Clean the product, confirm the dimensions

(o)  Proceed for water test.

Remarks:

1. Measure twice and cut one as improper measurement will waste material

2. Only pipe/plumbers vices to be used for pipe assembly

3. Wear gloves to protect your hands from GI burrs and swarfs.

4. Prepare packing for the union to prevent leakage.

The above work sheet enables the plumber to exhibit masterly of skills like measuring, cutting, interpreting working drawings,threading  and safety precautions. such practice should be under taken after the trainees have been introduced to measuring and marking, straight cutting (hack saw and blade or pipe cutter) and threading as we saw in the previous threading worksheet.

the trainees will find joy when they test for leakages and the assembly is found test free.

some time we will explain how to operate a hydraulic test pump.

try it out in your workshop and share with us how unions behave as you will try the assembly.

In case you would like to test, loosen the back nut of the union on the PVC loop and start pumping, this will allow escape of air from the pipework , after you see the first drop at this union, tighten the back nut and proceed pumping, check on your gauge.

waiting to share your experience and feed back

thank you so much.

prepared by 

Gilbert Niwamanya 

Instructor- Nakawa Vocational Training Institute 

Uganda.